1. Field of the Invention
This invention relates to a glass sight gauge for high pressure vessels. More specifically, this invention relates to sealing a cylindrical glass liquid level gauge to be used with liquid storage vessels containing a liquid under high pressure.
2. Description of the Prior Art
The basic concept of employing a vertical glass tube or glass windowed device attached to the outside of a liquid storage vessel to visually determine the liquid level within the container is generally known. It is further recognized that as the pressure of the vessel increases, conventional glass sight tubes ultimately fail (loss of seal or catastrophic failure). This is attributed to the build up of stress associated with pressuring up the vessel and sight gauge. The problem is further aggravated in situations involving storage of a high temperature liquid because of temperature gradient and dissimilar thermal expansion contributions to stress and lack of sealing around the glass tube.